As the offshore oil and gas exploitation advanced into the deepwater application, the traditional fixed production platform cannot meet the requirements of the deepwater oil and gas exploitation, and the floating production platform becomes currently the main equipment of the deepwater oil and gas exploitation. Recently, a variety of floating production platforms used in the deepwater oil and gas exploitation have been developed and applied into the deepwater oil and gas exploitation over the world, such as the semi-submersible platform, the deep draft spar platform, and the tension leg platform. Each of the above platforms has its own advantages and disadvantages: the semi-submersible platform has poor heaving motion performance, and when used as the deepwater oil and gas production platform, it has to be used with wet tree which is technically complex and costly; the deep draft spar platform has good motion performance and can employ the dry tree, however, it's disadvantages comprise: the topside and the lower hull thereof requiring separate offshore installation, the complexity of installation and connection offshore, the small area of the upper deck, difficulty of design, and difficulty of arrangement of the oil and gas processing facilities; and the tension leg platform also has good motion performance, however, since it connects to a seabed infrastructure via a tension leg, the cost would increase as the increase of water depth.
For such advantages and disadvantages of the platforms, many novelty technical solutions and new concepts have been proposed in the offshore engineering, however, such new concepts and the traditional platforms are installed complexly offshore and need to use large ocean engineering equipments for offshore installation, causing high cost.